In diamond tools’ manufacture, the hot press method has below advantages:

1) The pressure in hot press method is low, so the requirement to the press machine is also low, and graphite or cast-iron molds can be used instead of the ones made of high-strength alloy steel.

2) The bonding strength is high, so this method can be applied to produce complex-shape products and the reject rate can be lowered.

3) The products can be sintered with molds, so their expansion and contraction can be controlled and their sizes can be kept well. After stripping, there will be no elastic aftereffect on the pressed blanks.

4) The heating time is short and the production period is also short. This is convenient for small batch production.

5) The low pressure of this method reduces the possibility of diamonds’ crush.

6) The blank materials are sealed in molds, and will not contact with air. The heating time is short. Protective gas may not be used. These simplify the sintering process.

7) The sintering process can be better controlled.

The hot press method also has some disadvantages:

1) There are many production links in this method, and its production efficiency is not high.

2) This method needs many graphite molds, and needs many times of mold loading and stripping.

3) The graphite molds are apt to be damaged, for example, be burned to be defective or be cracked by expansion.